Question: $g(t) = 6t-f(t)$ $f(t) = 2t$ $ g(f(9)) = {?} $
Answer: First, let's solve for the value of the inner function, $f(9)$ . Then we'll know what to plug into the outer function. $f(9) = (2)(9)$ $f(9) = 18$ Now we know that $f(9) = 18$ . Let's solve for $g(f(9))$ , which is $g(18)$ $g(18) = (6)(18)-f(18)$ To solve for the value of $g$ , we need to solve for the value of $f(18)$ $f(18) = (2)(18)$ $f(18) = 36$ That means $g(18) = (6)(18)-36$ $g(18) = 72$